1. Field of the Invention
The present invention relates to an automatically driven motor vehicle, and more particularly to an automatically driven motor vehicle capable of automatically running within a lane on a road based on positional information obtained from the road.
2. Description of the Prior Art
Research efforts are being made to develop a technology for automatically driving motor vehicles such as automobiles on roads while detecting obstacles with a radar, a CCD camera, or their combination to recognize front obstacles and road conditions. However, there has not been available any technology, to be incorporated into automatically driven motor vehicles, for appropriately recognizing front obstacles and road conditions on any roads.
Automatic vehicle travel control under given conditions has already been practiced in limited applications such as automatic transport carriage control in factories, for example. Such an automatic transport carriage is controlled to travel at a low speed along a predetermined path based on the detection of magnetic markers that are arranged at given intervals along the path.
However, it is difficult to control the automatic transport carriage to run accurately on the predetermined path, and the actual position where the automatic transport carriage runs tends to be displaced in error from the predetermined path while the automatic transport carriage is running.
It has been customary to control the automatic transport carriage to run along the predetermined path by detecting a displacement error between the present position of the automatic transport carriage and the predetermined path and eliminating the displacement error under feedback control.
The conventional automatic transport carriage control process has been unstable because of hunting in eliminating displacement errors particularly when the automatic transport carriage runs at high speeds. It has been difficult to run the automatic transport carriage on general roads while controlling its speed.